Pipe coating apparatus



8- 1949- L. R. ROBINSON ET AL 2,478,711

' PIPE COATING APPARATUS Filed Dec 25, 1947 I5 Sheets-Sheet l Fig.l.

INVENTORS rence 5. Robinson 8: I

Aug. '9, 1949 L. R. ROBINSON ET AL PIPE COATING APPARATUS 3 Sheets-Sheet 2 Filed Dec. 23, 1947 INVENTORS Lawrence 6. Robinson 8| R. ROBINSON ETAL 2,478,711

PIPE COATING APPARATUS 3Sheets-Sheet 5 Filed Dec. 23, 1947 Patented Aug. 9, 1949 TIPE "COKTINGflPPARATUS -.-La;wrence HR- Robinsn, Mount --:.I1ebanon, and

Waiter S.. Lang,-. Pittsburgh, Pa., 1 assignors- "to Bitts'burghllfipe Cleanenflompany; Pittsburgh, Pa., a company of Pennsylvania .iApIiliUzttiDliDBhember 23, 194?? SI'i'aI'TNO. 793,47 2

The'object of-"the invention is etd -provide, in

pipecoating -iapparatus; for. idryiilslg the" inside of :aapipe before the-coating material:is.-.-.applied, wapplying the :coating :material and. for drying the coating material after it is-applied.

Othertobjects of-mthe invention williinepa-rt be .-obvious,-and will -in g)ar-t;a1:|pear hereinafter.

The invention, .-acc01dingly, c omprisesthe teat tures-of construction, combination of elements,

'andarrangements of parts which will be-exemplified in the constnuction hereinafter set torth and l-the scopeof the application ofwhich will-beindi- .vcated inlzheiclaims.

"For .alfilller understanding of. the nature. and -objects of the invention, reference shouldlbe .had

' to the following 'detail'ediflescrintion; taken in 7 connection" with the accompanying drawings, 4 in which:

fFi'gure 1 is a view, partly in section .andpartly 'inside elevation, of apipe' coa'ting apparatusidisposed in a "section of pipe 'showingl' details of. :the

structure and the m'an'nerin Wh'ihit is propelled y through" a'pipe;

Fig. 215 a viewfin section; along ithei'linlI- lI O'f Fig. '1; V

Figi 4 is 'a'viewfin sectionralong "the;Iine'IV+IV of Fig. 5 {and ofthe lamp structure :pro'vided for dryingfihe pipeand applied coating.

Referring now 150' Figure 1; "ll'ld'esfgnates ap'ipe '-sedti0n,-*such-= as" rnig'htbe' found-in-a water line or sewer, and -which needs to becoated fromtime to time to protec't it from bth'corrosion and-"erosiongand to lower the cdefiicient' of friction to :increase itswap'a'city for the handiing er fluids.

The pipe f coating appara'tus =comprisesa carriage best shown in Figs. 1, Z and B. Thecar- I riage cons'istsrniza: :fozsward spifierg -sh'own genczerally Lat .l:l., :-which has :four :radrtiting legs evenly spaced around the? pipe. :iIh'e lewemnairmfilegs I2 and :l 3 formiatsaddle'. afor warming a? tubular member N -which will-be described inum'ore detail -hereinafter. eAt-ithe lower;-.ends;d;lsre ilegs iliz and 1 3 .are -bifurcatedias shown andr have "wheels I 5 mounted therein. =.-'l3hese wheels -may bezmounted in --.any suitable manner welleknowmin fthe -iailt. .'Ihe4;w0 -upper-1egS 1| S and ilfhoiwthexcarriage LI are united by a .strap. whichtfits oven -.the :tubular member I4. The-endsiofit'he legs .IB and :l-hare also bifurcated and have wlsxels 4.5 amounted therein.

illustratdfthe wheels 21 5 ofl the cariniage -I contact thejr'pipe zorztubular. memberr'l'lleatriw" frinterv'als. The carriageshouldifitsnuglytin-rfiie mine; and. :in order toadapt;itheiapparatnseto difierentsizesxot'pipe; the legs l'2,-I.3; I-Ma'nda :l1 5 may bexmade adjustableuin any amanner'swell known in the art. In connecting theeadfileiprowided'on. the ilower pair of legs-i=2 andhl3nto the i "tubular member i 4; leg screws may beiemployed. The forward spider, shownligenerally-sat 11,; is nconne'cted'lto. a :trailing spider structnreashbwn generally at 4:9 in Fig, 3, bynmea'nssota support I i8. Thefsupport 1I8.seats:on ithe strannresadtlle .-extending between the-legs 20 and 2.1. i-ilhempper section of. the spider 19. :compr-ises'mwo deg? members 22 and 23 forming a V and connectedrto a motor casing' zllv byzzmeans ohlagsscrewsififi. A .do.uble.-.armed. brace -26-is bolted to. :thersnnport 4'8 and. the strap iextendingxbetween.:therslegdfifl wand 21 of the lower sectionof the spider 1|;9. .aEBhe doubleearmed brace-supportssaicylindricalunrem- -ber. to -be.- described in-detail hereinafter.

'Theapparatus -forapplyingthewcoatingimate- 7 rial isdisposed-ion the forwardior:leadingmndmf the carriage; and:is sup ortedmostlysbyithedeadring spider -I l. .Ihe apparatus --fioriidelivering,-ithe coating material comprises the. itubularri-member J 4. referred to "hereinbefore,nwhichcisxconneoted to the saddle extending between. the. ilegskl'h-and .-I 3 bylagscrews. Disposedon the tubulansmem- 30 her -I 4, just .forwardofitheqspider -|-l is-.- azchannelshaped annular :member 21 which tormswai'g-land.

I through which theecoating materialdsndelivered. Forward of the gland 2lkisnylindrical: membeniZ8 isirotatably-vmountedionlmemberi k4. As best shown :in' Fig .1. the cylindrical memhen'in and the gland-2:7 are .rab-beted,rat :29,:soias'=to m ake tight engagement. The tcylindricalz memheri is held in tight engagement with the; gland: 2FI iby means-0f a ring Sli' mountedontheitubnlarrmemms-ber- M and .held zin-,=position loy -a lages'crewrw I. Inorder to rotate the cylindricalimembefiifl; a

.- :ring. ;gear.-32 is. mounted. thereoniandsattached thereto .in -any suitable mannen-fias ihyimreansiof .a, keyinot shown). The number 101?: :teeth-iproividedrin .the ring gearwilldependnpon theispeed at which :the cylindricalimemberi-i'is to-beidniven.

A delivery head- 33=-is prov-ide'd on the cylindricalamember 25. -As shown; theideliveryshead: is attached to the-cylindricalmember 24 hyE-means 50. of. a. flange amattached ito thet-cylindnical -member by dag screws: 35. t

i Communication between the-gland 221:1and the delivery head flame-established bywdr iilingsnn opening 36in the cylindrical :memberzsflilmwhich communicates with the-channeie kinsthe delivery head.

.The coating material-,c'such asipaint orza liquid bituminous materiaL- may be =deliveredwtoxithe fi-gland 2:1through-a pipe 3 8. F'Ihe souroe ofrfthe --coa.ting' materia1 .is not illustrated sincesadsank .iinewhich the coating material may he gantamsrder pressure or other suitable means well known in the art may be employed for delivering the coating material through the pipe 38. In order to drive the delivery head 33, and if desirable the whole carriage, a motor 39 is employed and disposed on the support l8.

A pinion 46 is mounted on the forward end of the motor shaft which meshes with another gear 4| mounted on a jack shaft 42 which is disposed in a bearing 43 provided on the cylindrical member l4. The bearing 43 may be any well-known type and its support cast integral with tubular member l4. In order to provide a suitable gear drive and proper speed, a pinion 44 is mounted on the forward end of the jack shaft 42 to mesh with another gear 45 carried by a jack shaft 46 rotatably mounted in a bearing 41 disposed in the leading spider II. On the forward end of the jack shaft 46 is another pinion 48 which meshes with the ring gear 32.

The drive for the delivery head may be traced from the motor 39 through pinion 4!], gear 4|, jack shaft 42, pinion 44, the gear 45, jack shaft 46, the pinion 48 on the forward end of the jack shaft 46, to the ring gear 32. As the ring gear 32 is driven, the cylindrical member 28 is rotated, swinging the delivery head 33 around the inside of the pipe as the carriage moves forward.

As is well-known, the inside of pipe lines buried underground or in certain plants are damp. When coating material, such as paint and bitumen and the like, are applied to damp surfaces, they do not adhere as tenaciously as desired. Therefore, before coating material is applied to the inner surfaces of water pipes and sewers, it is highly desirable that they be rendered as dry as possible. In this particular pipe coating apparatus, a drying unit is disposed in the lead of the coating apparatus. In this embodiment of the invention, a drying unit, which comprises a double ring of infra-red lamps, is provided. However, it is to be understood that any other suitable drying means, such as the well-known resistance heating elements employed in ovens, or any other suitable means for driving off moisture, may be employed.

In this particular coating apparatus, rings of infra-red lamps have been utilized because of the facility with which they may be mounted and the ease with which they may be focused to heat the pipe or sewer. The leading heating unit, shown generally at 49, is similar in construction to the trailing heating unit shown generally at 58. Both heating units comprise cylindrical members 5| which carry reflectors 52. The leading heating unit 49 is disposed on the tubular member |4. Any suitable method wellknown in the art may be employed for support ing the cylindrical member on the tubular member M. A trailing heating unit 58 is supported on the trailing spider I9 by the double-armed bracket 26, best shown in Fig. 3.

Since the two heating units are similar in construction, it will suifice to describe one in detail.

Referring now to Figs. 4 and 5, each heating unit 4'9 and 50 comprises two rings 53 and 54 of infra-red lamps. As shown, each ring comprises twenty-four lamps. The number of infrared lamps will depend upon the size of the heating unit it is desired to provide, and the size of the unit will depend on the work at hand. The cylindrical members 5| which carry the lamps and their reflectors 52 may be made of any suitable material. If made of a metal, it will be necessary to insulate the connections for the lamps; while, if they are made of some suitable insulating composition, the problem of insulating the connections for the lamps is easier. The reflectors 52 may be made of some suitable reflecting metal well-known in the art. These reflectors are mounted outside of the cylinders 5| on supports 55.

In order to supply the rings of infra-red lamps, any suitable supply system may be provided. In this particular instance, since there are two rings of lamps in each heating unit, a three-wire system will be employed. In order to connect the lamps to the three-wire system, conducting rings 56, 5! and 58 are disposed on the cylinders 5|. These conducting rings may be connected to a three-wire system in any suitable manner, making the central ring 51 the neutral and the 110- volt lines being connected to the conductin rings 56 and 58.

The sockets '59 for the infra-red bulbs of the rings 53 and 54 are mounted on plates 68 carried by the cylindrical members 5|. These sockets may be mounted in any suitable manner wellknown in the art.

In order to supply the lamps, conducting straps 6| are connected between one terminal of the sockets 59 and the supply rings 56 and 58. Of course, in making these connections, it is necessary to insulate the rings 56, 5'! and 58 from the cylindrical member 5| if it is metal. Methods for doing this are well-known in the art. The other terminals of the sockets 59 are connected by the long straps 62 to the neutral ring 51. In this manner, any predetermined number of bulbs in each of the rings 53 and 54 may be supplied with the necessary current for energizing them. Any suitable means well-known in the art (not shown) may be provided for turning the electric current on and off, as needed in the operation of the pipe coating apparatus.

The current for operating the motor 39 and for supplying the heating units 49 and may be supplied through any suitable conductors well-known in the art. It is known to provide supply conductors on drums so that the pipe coating apparatus may be moved along the pipe as desired, the drum serving to play out the conductors'as the carriage moves forward, and to reel them in as the carriage is drawn back.

In the operation of the pipe coating apparatus, the leading heating unit subjects the section of the pipe to be coated immediately ahead of the delivery head 33 to intensive heating for a short time. It has been found by experiment that unless some unusual conditions exist, the pipe can be dried sufliciently to properly receive the coating of paint or bitumen so that it will adhere tenaciously.

As the carriage moves forward, the pipe that has been dried and heated by the leading heating element 49 is coated through the delivery head 33. As has been pointed out hereinbefore, the delivery head is driven from the motor 39 through a train of gears. The delivery head rotates around the tubular member l4 and delivers the coating material in something of a spiral as the pipe coating apparatus is moved forward.

The speed of the carriage can be related to the speed of the delivery head so that all of the inside of the pipe will be covered with the coating material delivered from the head 33. Means for moving the carriage forward at a predetermined speed, so that all of the inside of the pipe will be subjected to coating material, are well-known in the art.

The coating material supplied through the pipe 38 may be delivered under pressure, and the coating material discharged by means of compressed air. This is common practice in the art.

Since certain changes may be made in the above device and different embodiments of the invention can be made without departing from the scope thereof, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

We claim as our invention:

1. In pipe treating appartus, in combination, a carriage disposed to be propelled through the pipe, a heating unit for drying the pipe disposed on the leading end of the carriage, a pipe coating device carried by the carriage and following the heating unit, and a second heating unit disposed on the rear end of the carriage following the pipe coating device for drying the coating material applied to the inside of the pipe loy the pipe coating device.

2. In pipe treatin apparatus, in combination, a carriage adapted to be propelled through a pipe to be treated, a radiant heating unit at one end of the carriage for drying the pipe, a pipe coating unit disposed to follow the radiant heating unit to coat the pipe as it is dried, and a second radiant heating unit trailing the pipe coating unit to dry the coating material applied to the inside of the pipe.

3. In pipe treating apparatus, in combination,

a carriage adapted to be propelled through the pipe to be treated, a radiant heating unit disposed in front of the carriage to dry the pipe to be treated, means for applying a coating material mounted on the carriage to coat the pipe dried by the heating unit, a second radiant heating unit disposed on the carriage trailing the means for coating the pipe for drying the coating material, and means for supplying coating material to the pipe coating apparatus and actuating the pipe coating apparatus.

4. In pipe treating apparatus, in combination, a drying unit for drying the pipe to be treated, coating mechanism trailing the drying unit, a second drying unit following the coating apparatus to dry the coating material, the drying units and coating mechanism being so connected that they move in a predetermined spaced relation, and means for operating the coating apparatus at a predetermined speed to correspond with the rate at which the pipe is dried.

5. In pipe treating apparatus, in combination, a plurality of infra-red bulbs arranged in a ring for drying the inside of a tubular member, coating apparatus for applying a coating material to the inside of the pipe as it is dried, a second heating unit or infra-red lamps arranged in a ring to dry the coating material applied to the pipe, means for maintaining the dryin units and the coating apparatus in a predetermined cooperative spaced relationship and means for operating the coating mechanism and for propelling the drying units and coating mechanism through a pipe.

6. In pipe treating apparatus, in combination, an infra-red heating unit having the infra-red lamps arranged in circular banks for drying the pipe, a carriage for carrying the infra-red heating unit, pipe coating mechanism carried by the carriage and disposed to follow the infra-red heatin unit, a second infra-red heating unit disposed on the carriage and following the pipe coating mechanism, and means for actuating the pipe coating mechanism to apply coating material as the carriage is propelled through the pipe.

'7. In pipe treating apparatus, in combination, a carriage adapted to be propelled through a pipe, an infra-red heating unit disposed on the forward end of the carriage, the infra-red heating unit comprising rings of infra-red lamps for drying the pipe, a delivery head for delivering coating material to the inside of the pipe rotatably disposed on the carriage, an annular gland disposed to communicate with the delivery head as the latter is rotated to coat the inside (21 the pipe, means for supplying coating material to the annular gland as the delivery head rotates, a second infra-red heating unit disposed on the carriage to trail the delivery head, the second heatin' unit comprising rings of infra-red lamps disposed to dry the coating material as it is applied by the delivery head, and means for actuating the delivery head as the carriage is moved through the pipe.

8. In pipe treating apparatus, in combination, a carriage adapted to be moved through a pipe, a support disposed on the carriage and extending forward, an infra-red heating unit mounted on the forward end of the support, the infra-red heating unit comprising a ring of infra-red lamps disposed in a ring for heating the inside of a pipe, reflectors disposed inside of the ring of infra-red lamps to direct the rays against the pipe, means for coating the pipe with a coating material disposed on the carriage and trailing the heating unit, a second heating unit mounted on the carriage trailing the pipe coating apparatus, the second heating unit comprising a ring of infra-red lamps, a reflector for directing the rays outwardly against the pipe, and means for actuating the coating mechanism.

9. In pipe treating apparatus, in combination, a carriage adapted for movement in a pipe, a support carried by the carriage, the support extending forwardly of the carriage, an infra-red heating unit carried by the support, the infrared heating unit including a plurality of lamps arranged in a ring, reflectors disposed inside of the infra-red lamps for directing the rays against the pipe, a rotatably mounted delivery head for delivering coating material to the inside of the pipe, a drive for actuating the rotatably mounted delivery head, an annular gland for maintaining communication with the delivery head as it rotates, a supply pipe for delivering coating material to the gland, means for actuating the delivery head to coat the inside of the pipe, a second infra-red heating unit, the lamps of the infra-red heating unit being arranged in a ring, a reflector disposed inside of the lamps to direct the infra-red rays against the coating material to dry it, and means for actuating the delivery head disposed on the carriage inside the second infra-red heating unit.

LAWRENCE R. ROBINSON. WALTER S. LANG.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,125,025 Huckfeldt et a1 July 26, 1938 2,132,391 Boylan Oct. 11, 1938 2,337,740 Albright Dec. 28, 1943 

